Optical fibers are well known which comprise a transparent glass or plastic core and a cladding covering the core concentrically therewith and having a lower refractive index than the core material, such that when light incidents on one end of the fiber, light travels through the fiber while being totally reflected in its interior.
Many of the polymers, such as fluoroalkyl methacrylate polymers, have been heretofore proposed for use as plastic cladding materials. However, these methacrylate polymers still remain to be improved in softening temperature, decomposition temperature, refractive index and other properties which are required of cladding materials for optical fibers.